U.S. patent number 8,957,258 [Application Number 14/357,861] was granted by the patent office on 2015-02-17 for bis(1,1-dichloro-3,3,3-trifluoropropyl) ether and process for preparing the same.
This patent grant is currently assigned to Kanto Denka Kogyo Co., Ltd.. The grantee listed for this patent is Kanto Denka Kogyo Co., Ltd.. Invention is credited to Toshiaki Okamoto, Chizuko Okazaki.
United States Patent |
8,957,258 |
Okamoto , et al. |
February 17, 2015 |
BIS(1,1-Dichloro-3,3,3-trifluoropropyl) ether and process for
preparing the same
Abstract
The present invention provides a symmetrical ether compound
which is chlorinated in the .alpha. position and which is useful as
an intermediate for medicine and pesticides and as a raw material
or a synthetic intermediate for producing a fluorine-containing
compound, in particular a
bis(1,1-dichloro-3,3,3-trifluoropropyl)ether represented by formula
[1] which is obtained by chlorinating a
bis(3,3,3-trifluoropropyl)ether. This
bis(1,1-dichloro-3,3,3-trifluoropropyl)ether is produced by
chlorinating, preferably under ultraviolet light irradiation, a
bis(3,3,3-trifluoropropyl)ether [1].
Inventors: |
Okamoto; Toshiaki (Okayama,
JP), Okazaki; Chizuko (Okayama, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
Kanto Denka Kogyo Co., Ltd. |
Tokyo |
N/A |
JP |
|
|
Assignee: |
Kanto Denka Kogyo Co., Ltd.
(Tokyo, JP)
|
Family
ID: |
48873415 |
Appl.
No.: |
14/357,861 |
Filed: |
January 21, 2013 |
PCT
Filed: |
January 21, 2013 |
PCT No.: |
PCT/JP2013/051057 |
371(c)(1),(2),(4) Date: |
May 13, 2014 |
PCT
Pub. No.: |
WO2013/111695 |
PCT
Pub. Date: |
August 01, 2013 |
Prior Publication Data
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|
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Document
Identifier |
Publication Date |
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US 20140336419 A1 |
Nov 13, 2014 |
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Foreign Application Priority Data
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|
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Jan 24, 2012 [JP] |
|
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2012-011936 |
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Current U.S.
Class: |
568/684 |
Current CPC
Class: |
C07C
43/123 (20130101); C07C 41/22 (20130101); C07C
41/22 (20130101); C07C 43/123 (20130101) |
Current International
Class: |
C07C
43/12 (20060101); C07C 41/22 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
|
|
|
|
|
62-230886 |
|
Oct 1987 |
|
JP |
|
2000-351751 |
|
Dec 2000 |
|
JP |
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2007-501844 |
|
Feb 2007 |
|
JP |
|
Other References
John A. Young et al., "The Preparation of Some Derivatives of
Chlorofluoroacetic Acid", Journal of the American Chemical Society,
vol. 71, Jul. 1949, pp. 2432-2433. cited by applicant .
John A. Young et al., "New Method of Preparation of Esters of
Difluoroacetic Acid", Journal of the American Chemical Society,
vol. 72, Apr. 1950, pp. 1860-1861. cited by applicant .
Wojciech Dmowski et al., "Reactions of Sulfur Tetrafluoride With
Carboxylic Acids", Polish Journal of Chemistry, 52, 71, 1978, pp.
71-85. cited by applicant .
International Search Report, PCT/JP2013/051057, Apr. 16, 2013.
cited by applicant .
Edited by the Chemical Society of Japan, 4th edition Jikken Kagaku
Koza 21, published by Maruzen Co., Ltd 1990, Nen, pp. 179 to 181.
cited by applicant.
|
Primary Examiner: Davis; Brian J
Attorney, Agent or Firm: Young & Thompson
Claims
The invention claimed is:
1. Bis(1,1-dichloro-3,3,3-trifluoropropyl) ether represented by
formula (1): ##STR00005##
2. A process for preparing bis(1,1-dichloro-3,3,3-trifluoropropyl)
ether comprising chlorinating bis(3,3,3-trifluoropropyl) ether
represented by formula (2): ##STR00006##
Description
TECHNICAL FIELD
This invention relates to bis(1,1-dichloro-3,3,3-trifluoropropyl)
ether and a process for preparing the same.
BACKGROUND ART
Non-patent documents 1 to 3 below disclose an ether compound having
a 1,1,3,3,3-pentafluoropropyl group which is analogous to the ether
compound of the invention. However, these documents have no mention
of a symmetrical ether compound having its .alpha.-positions
chlorinated like the ether compound of the invention.
LIST OF CITATION
Non-Patent Document
Non-patent document 1: Journal of the American Chemical Society 71,
2432 (1949)
Non-patent document 2: Journal of the American Chemical Society 72,
1860 (1950)
Non-patent document 3: Polish Journal of Chemistry 52(1), 71-85
(1978)
SUMMARY OF THE INVENTION
Problem to be Solved by the Invention
An object of the present invention is to provide a symmetrical
ether compound having the .alpha.-positions chlorinated that is
useful as an intermediate of pharmaceuticals and agricultural
chemicals or a starting material or an intermediate for
synthesizing fluorine-containing compounds.
Means for Solving the Problem
The inventor has conducted extensive study to solve the above
problem and as a result succeeded in synthesizing a novel
symmetrical ether compound having the .alpha.-positions chlorinated
and found that the ether compound accomplishes the above object of
the invention. The invention has been completed based on this
finding.
The invention provides bis(1,1-dichloro-3,3,3-trifluoropropyl)
ether represented by formula (1):
##STR00001##
The invention also provides a process for preparing
bis(1,1-dichloro-3,3,3-trifluoropropyl) ether represented by
formula (1). The process comprises chlorinating
bis(3,3,3-trifluoropopyl) ether represented by formula (2):
##STR00002##
Effect of the Invention
Bis(1,1-dichloro-3,3,3-trifluoropropyl) ether of the invention is
an extremely important compound as an intermediate for
pharmaceuticals and agricultural chemicals or a starting material
for synthesizing fluorine-containing compounds having a
trifluoromethyl group at the terminal.
BEST MODE FOR CARRYING OUT THE INVENTION
Bis(1,1-dichloro-3,3,3-trifluoropropyl) ether and a preferred
embodiment of a process for preparing the same according to the
invention will be described. It should be noted, however, that the
invention is not deemed to be limited thereto, and various changes
and modifications can be made therein without departing from the
spirit and scope thereof.
[1] Structure
Bis(1,1-dichloro-3,3,3-trifluoropropyl) ether of the invention is a
symmetrical ether compound having the .alpha.-positions thereof
chlorinated, being represented by formula (1).
##STR00003##
[2] Properties
The ether compound of the invention is a colorless transparent
liquid compound and stable per se.
[3] Use
It is possible that the ether compound of the invention have its
.alpha.-positions converted to carbonyl by hydrolysis. the ether
compound is easier to handle than heretofore reported intermediates
for fluorine-containing compounds or fluorinating agents because of
its high stability and resultant low risk. The carbonyl compound
obtained by hydrolysis is useful as a starting material or
intermediate for pharmaceuticals and agricultural chemicals.
Understandably, the ether compound of the invention is also useful
as an intermediate for the syntheses.
[4] Process for Preparation
Bis(1,1-dichloro-3,3,3-trifluoropropyl) ether of the invention is
obtained by chlorinating the .alpha.-positions of
bis(3,3,3-trifluoropropyl) ether represented by formula (2), which
is synthesized by a known process, as shown in reaction scheme 1
below.
The known process for synthesizing bis(3,3,3-trifluoropropyl) ether
of formula (2) is exemplified by the process described in Journal
of Organic Chemistry 28, 492 (1963).
##STR00004##
The manner of chlorination reaction is not particularly limited.
For example, the chlorination reaction can be carried out by
causing chlorine to react on bis(3,3,3-trifluoropropyl) ether in a
liquid or gas phase using a radical initiator or under UV
irradiation. The process comprising causing chlorine to react under
UV irradiation is preferred.
That is, bis(1,1-dichloro-3,3,3-trifluoropropyl) ether of the
invention is prepared by causing chlorine to react on
bis(3,3,3-trifluoropropyl) ether under UV irradiation.
Preparation of bis(1,1-dichloro-3,3,3-trifluoropropyl) ether of the
invention will be described in detail with reference to the process
comprising causing chlorine to react on bis(3,3,3-trifluoropropyl)
ether under UV irradiation.
Chlorine that can be used in the invention preferably has a
concentration of 10% to 100%, more preferably 90% to 100%. Chlorine
is used in an amount preferably of 4 to 10 mols, more preferably 4
to 5 mols, per mole of the reaction substrate.
The reaction temperature is preferably -20.degree. to 50.degree.
C., more preferably 0.degree. to 20.degree. C. At 70.degree. C. or
higher temperatures, is unfavorable because
bis(1,1-dichloro-3,3,3-trifluoropropyl) ether decomposes by the
action of by-produced (by product) hydrogen chloride.
In order to increase the chlorination efficiency, it is preferred
that the substrate and chlorine be allowed to react with each other
in a liquid phase under UV irradiation. The reactor to be used may
be, for example, a glass vessel equipped with a light source. While
the reaction proceeds even under UV light from outside the reactor,
it is preferred to use a light source inserted inside the reactor
from the viewpoint of light use efficiency. Example of suitable
light sources are a high, ultrahigh, or low pressure mercury lamp
and a UV LED.
The wavelength of the UV rays for use in the reaction is preferably
312 to 577 nm, more preferably 312 to 493 nm.
The reaction does not need a reaction solvent but can carried out
in a solvent inert to the reaction. Examples of useful solvents are
water, carbon tetrachloride, dichloromethane, and mixtures
thereof.
As the reaction proceeds, the hydrogen chloride is by-produced (by
product). It is advisable that the generated hydrogen chloride be
released from the reaction system and absorbed by water, an aqueous
alkali solution, or the like.
After completion of the reaction, chlorine remaining in the
reaction mixture is expelled by bubbling with nitrogen. The
by-produced (by product) hydrogen chloride is then removed by the
addition of an aqueous basic solution, such as a potassium
hydroxide aqueous solution. Subsequently, a sodium sulfite aqueous
solution is added to reduce any residual chlorine. The lower liquid
phase is collected to yield a desired product, which is purified by
distillation.
In the case when the chlorination reaction is carried out using a
radical initiator, the reaction can be performed according to a
conventional manner for chlorination using a radical initiator.
After the reaction, the reaction mixture is worked up in the same
manner as described with respect to the chlorination reaction under
UV irradiation.
Examples of the radical initiator include azobisisobutyronitrile
and benzoyl peroxide.
EXAMPLES
The invention will now be illustrated in greater detail with
reference to Example, but the invention is not construed as being
limited thereto.
Example 1
Synthesis of bis(1,1-dichloro-3,3,3-trifluoropropyl) ether
In a glass-made 200 ml-photoreactor equipped with a stirrer, a
thermometer, a 100 W high pressure mercury lamp, a Dimroth
condenser, and a chlorine gas inlet tube were put 210 g (1.00 mol)
of bis(3,3,3-trifluoropropyl) ether and cooled in an ice/water
bath. The high pressure mercury lamp (UVL100HA from Riko Kagaku
Sangyo K.K.) was turned on to irradiate the reaction mixture with
UV light of 312 to 577 nm. Into the reaction system was introduced
5.10 mol of chlorine at a rate of 480 ml/min over 5 hours while
stirring the mixture using a magnetic stirrer. The chlorination
reaction temperature reached 20.degree. to 30.degree. C. as a
result of reaction heat. After completion of the reaction, the
reaction mixture was analyzed by gas chromatography. The starting
material, bis(3,3,3-trifluoropropyl) ether, was not detected. The
gas chromatographic area percent of
bis(1,1-dichloro-3,3,3-trifluoropropyl) ether was found to be
83.0%.
Nitrogen was made to flow through the reaction mixture, and water
was added thereto. Residual chlorine was removed by reduction using
a 10% sodium sulfite aqueous solution and a 48% potassium hydroxide
aqueous solution while stirring in an ice/water bath, followed by
liquid-liquid separation to collect a desired product, which was
dried over sodium sulfate. Following the removal of the desiccant
by filtration, the ether solution was distilled under reduced
pressure to collect a fraction having a boiling point of 70.degree.
to 71.degree. C. (1 kPa) to give 230.75 g of
bis(1,1-dichloro-3,3,3-trifluoropropyl) ether in a yield of 65%.
The gas chromatographic area percent of the fraction was 98.1%. The
spectral data of the resulting
bis(1,1-dichloro-3,3,3-trifluoropropyl) ether are shown below.
1H-NMR spectrum (500 MHz, CDCl.sub.3) .delta. (ppm): 3.39 (4H, q,
J=9.0 Hz)
19F-NMR spectrum (470 MHz, CDCl.sub.3) .delta. (ppm): -62.0 (6F, t,
J=9.0 Hz)
MS spectrum (m/z): 165 (CF.sub.3CH.sub.2CCl.sub.2), 111
(CF.sub.3CH.sub.2CO), 83 (CF.sub.3CH.sub.2), 69 (CF.sub.3).
* * * * *